Method for establishing a default connection in network, and associated source and sink devices

ABSTRACT

A sink device for connection to a digital network comprising means for displaying a user interface for controlling a data source device connected to the network; characterized by: means for controlling network resource allocation and for automatically establishing, upon selection of a function of the source device by the user through the user interface, a connection between the data source device and the data sink device as default destination device of the connection, wherein said sink device has playback capability of the data of the source device.

FIELD OF THE INVENTION

The invention relates to a home network and the establishment ofconnections between devices in this network. More particularly theinvention concerns a network of multiple electronic devices, such asconsumer electronic video source and video display devices,interconnected using for example digital data buses.

BACKGROUND OF THE INVENTION

In a home network, electronic devices such as television receivers,display devices, video-cassette recorders (VCR), direct broadcastsatellite (DBS) receivers, and home control devices (e.g., a securitysystem or a temperature control device) may be interconnected via a databus. Communication using a data bus occurs in accordance with a busprotocol. Examples of bus protocols include the Consumer Electronics Bus(CEBus) and the IEEE 1394 High Performance Serial Bus.

A bus protocol typically provides for communicating both controlinformation and data.

Unlike analogue connections between two devices, in which the connectionlink itself defines the start and end points for a communication betweenthe devices, a digital bus connection between devices may not obviouslydefine how the devices are to communicate between each other. Thereforeit is necessary to explicitly set which devices are to communicatebetween each other.

The international patent application published under referenceWO99/14946 relates to consumer electronic devices connected over adigital bus, i.e., the IEEE 1394 serial bus. Remote control commandsgiven by a user through a display device are relayed to the controlleddevice over the serial bus. The display device may set up isochronousconnections.

The European patent application published under reference EP1056021 A2relates to electronic equipment for use with a communication systemconnected by a communication bus such as an IEEE 1394 bus. Each of theequipment connected to an IEEE 1394 bus may include a register providedwithin a RAM to thereby set a transmission or reception default channel.If channels used in the transmission and the reception are not set whenthe transmission is started, then the default channel may be used.

SUMMARY OF THE INVENTION

The invention concerns a sink device for connection to a digital networkcomprising:

means for displaying a user interface for controlling a data sourcedevice connected to the network;

characterized by:

means for controlling network resource allocation and for automaticallyestablishing, upon selection of a function of the source device by theuser through the user interface, a connection between the data sourcedevice and the data sink device as default destination device of theconnection, wherein said sink device has playback capability of the dataof the source device.

The sink device becomes the default destination of the data of thesource device as soon as the source device is selected through the userinterface of the sink device. Thus, the user does not have to explicitlyselect the display device he is watching as the sink device for the datato be transmitted.

According to an embodiment of the invention, the connection is anisochronous transmission connection comprising allocation of a channeland of bandwidth.

According to an embodiment of the invention, the controlling means ofthe sink device carry out a check for an existing connection from thesource device to another sink device, and in the affirmative, do notautomatically set up the connection between the source device and thesink device.

According to an embodiment of the invention, the selected function is aplayback function.

This is advantageous in particular when the source device is a storagedevice requiring control of playback through start/stop type controls.Indeed, in such a case, it is not necessary to set up a connectionbefore the actual playback starts (instead of setting up the connectionearlier, for example when the source device is selected through the userinterface).

According to an embodiment, the function is a selection function of thesource device. This case is more adapted to devices capable ofcontinuously outputting data, such as a tuner.

According to an embodiment of the invention, the sink device furthercomprises memory for storing software downloaded from the source device,wherein said software is adapted to control the automatic establishmentof the connection between the source device and the sink device andwherein said user interface is derived from said software.

Consequently, it becomes easy to adapt the connection set-up process tothe device type, since different devices may include different software.

The invention also concerns a method for setting up a data streamconnection in a digital network comprising a source device and a sinkdevice, said method comprising the steps of:

-   -   executing a user interface on the sink device;    -   selecting a function of the source device through the user        interface;

characterized by the step of:

-   -   establishing a connection for data transmission from the data        source device to the data sink device as default destination        device of the connection, wherein said sink device has playback        capability of the data of the source device.

The invention also concerns a data source device for connection to acommunication network comprising at least one sink device, said datasource device comprising software for downloading by a sink device, saidsoftware providing control functions of the data source device foraccess by a user through the sink device, characterized in that saidsoftware is adapted to the control of automatically establishing, uponselection of a data reproduction function by a user, a connection fortransmission of data from the data source device to the sink device onwhich the reproduction function was selected.

BRIEF DESCRIPTION OF THE FIGURES

A nonrestricting embodiment of the invention will now be described ingreater detail with reference to the accompanying drawings, in which

FIG. 1 contains a schematic representation of a digital home networkaccording to the embodiment;

FIG. 2 contains a flow chart illustrating a process for setting a dataflow connection according to the embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

One example of a home network in which the devices are connected over anIEEE 1394 digital bus is described in the HAVi digital AV networkinginitiative. HAVi is an industry standard that provides a home networkingsoftware specification for seamless interoperability among homeelectronic consumer devices, mainly digital audio and video devices.HAVi defines an operating-systerneutral middleware that managesmulti-directional AV streams, event schedules, and registries.Furthermore HAVi provides Application Programming Interfaces (API) forcreating software applications.

As each device is added and connected to a HAVi network system, it isautomatically registered by the system so that other devices know whatit is capable of. A newly connected device may provide a Graphical UserInterface (GUI) by means of a Havlet, i.e., a module of code which isdownloaded from the newly connected device by devices already connectedon the network. More precisely, a newly connected device may becontrolled through any other connected device that executes the Havletand possibly displays the corresponding GUI.

As an example, a newly connected DVCR may provide a Havlet on a networkwhich comprises a DTV. After automatic registration of the DVCR in theHAVi network system, the DVCR may be selected on the screen of the DTV.Subsequently the Havlet of the DVCR is downloaded to the DTV. Theexecution of the Havlet results in the corresponding GUI being displayedon the screen of the DTV. The GUI offers possibilities to control theoperation of the DVCR. A user may for example through the GUI select toplayback video information available through the DVCR.

The Havlet on the DTV first checks for the existence of an isochronousconnection between the DVCR and a target/sink device other than the DTV.If such a connection exists, then no further isochronous connection isautomatically set up. Transmission over the existing channel andplayback on the sink device can start.

In order to play back video information from the DVCR, the Havlet on theDTV checks whether an isochronous data flow exists between the DVCR andthe DTV. If this is the case, playback starts.

In case there is no isochronous data flow set up between both devices,the Havlet uses a stream manager of the DTV that sends controlinformation to the DVCR in order to establish an sochronous data flowconnection between them. The stream manager requests allocation of anisochronous channel and of corresponding bandwidth, and then modifiesthe concerned output plug control register of the DVCR by asynchronoustransactions on the IEEE 1394 serial bus. The stream manager therebysets an oPCR of the DVCR to transmit over a determined channel, and aniPCR of the DTV to receive over the determined channel. The streammanager also instructs respective DCMs of the DVCR and of the DTV to setup the internal connections in these devices, between the plugsmentioned above, and the FCMs of the devices. Once the isochronousconnection is in place, the playback starts.

It has been described how to automatically establish an isochronous dataflow between a device to be controlled, and between a device which hasdownloaded and is executing the Havlet from the device to be controlled.The described process assures that the device which executes the Havletis considered as default device for communication with the deviceissuing the Havlet, in the absence of any indication to the contrary.Note that the default playback device is not predefined in the Havlet:it is the device executing the Havlet. The process eliminates the needto manually set an isochronous data flow between devices. The processmay also overrun an initial default setting of the devices for using adefault communication channel, the initial default settings existingbefore the concerned device is connected to the network.

It has been further described to make use of an Havlet to produce a GUIthat offers possibilities to control the operation of the DVCR.

As an alternative, a proprietary GUI included in the DTV could offersimilar possibilities to control the operation of the DVCR. In this caseno Havlet is downloaded to the DTV. However, the Havlet solution ispreferred: since the Havlet itself is in control of establishing theconnection between the source device and the display device, it ispossible to adapt the behaviour for each individual source device. I.e.one DVCR may comprise a Havlet creating automatically the connection,while a second DVCR may comprise a Havlet that does not create theconnection.

Moreover, the invention applies to other environments than HAVi: otherdownloadable executable programs than a Havlet may carry out similarfunctions in these environments.

Referring to FIG. 1, a schematic representation of a digital homenetwork 100 comprises a digital bus 101 to which a Consumer ElectronicDevice A (CED-A) is connected. The CED-A is capable of rendering Audioand Video type information such as for example movies or sound records.It comprises a display 102 and a memory 103 under the control of amicroprocessor 104. Microprocessor 104 runs programs stored in memory103. CED-A is for example a digital television receiver (DTV). CED-B isa storage device with playback capability, such as a digital videocassette recorder (DVCR). It comprises a Havlet 105 in a memory (notillustrated) accessible by other devices of the network.

Referring to FIG. 2, a flow chart illustrates the establishment of adefault connection between CED-A and CED-B. After CED-B is connected tothe digital data bus, event messages are generated to announce the newsoftware elements (e.g. functional component modules) of the new device.CED-A now knows that the device CED-B is connected to the network andmakes its availability known to the user by displaying CED-B in a liston the TV screen (box 202). A user selecting CED-B (box 203) causesCED-A to download a Havlet 205 from CED-B. More precisely CED-A sends arequest (box 206 and 207) to CED-B, that in answer returns (box 208) theHavlet 205. The Havlet 205 is received and processed by CED-A (box 209).The processing of Havlet 205 results in the display of a Graphical UserInterface for CED-B by CED-A (box 210 and 211). The GUI enables accessto services offered by CED-B by producing a display of control functionsaccessible to the user at CED-A. Hence the user may send controls fromCED-A to CED-B to control for example the playing of AV data.

A user instruction 212 selected on the GUI 211 instructs to play AV datafrom CED-B. The instruction is processed by CED-A (box 213) and thenecessary action to establish a data flow connection with CED-B is taken(box 214) by sending control data 215 to CED-B. Connection parametersare set in CED-A and CED-B as appropriate to create the connection asrequired by CED-A (box 216). Once the data flow connection isestablished, the user instruction is forwarded to CED-B (box 217) as aplay instruction 218 that is in a format usable by CED-B (i.e. andappropriate API method call). The play instruction 218 is received andprocessed by CED-B (box 219), that in turn outputs (box 220) requestedAV data 221. The CED-A processes the AV data for rendering (box 222) andgenerates AV output 223.

Hence when CED-B is connected to the digital home network, and a datarendering function from CED-B is selected through a GUI displayed byCED-A, any AV output from CED-B is automatically directed to CED-A forrendering.

It has been described to automatically establish a data flow connectionafter an instruction to play AV data from CED-B has been given. In analternative embodiment of the invention, the data flow may well beestablished before an instruction to play AV data is given. In this casethe connection is automatically established as a result of theprocessing in CED-A of the Havlet from CED-B. Note that this alternativeembodiment is more adapted to functional component modules that do nothave a start playback /stop playback feature, such as a tuner. For afunctional component module having the start/stop feature, reservationshould only be done when required (e.g. when reproduction of an A/Vprogramme is requested) to avoid tying up the limited isochronousresources unnecessarily. A reserved channel and its associated bandwidthcannot be reallocated until they are released, even if the bandwidth isnot used at all or not to its full extent. For a tuner, selection of thecorresponding device (or launching of the corresponding Havlet) issufficient to trigger the automatic channel set up, since no furthercommand has to be given by the user to start the data transmission.Again, the fact that the Havlet controls the triggering of the automaticconnection is an advantageous feature in such a case.

The behaviour relative to a tuner type device compared to a DVCR typedevice is then the following:

(a) No connection exists to the display device (e.g. the DTV)

If the user selects the tuner, a connection is created from the tuner tothe display device

If the user activates playback of the DVCR, a connection is created fromthe DVCR to the display device

(b) A connection exists between the tuner type device and the displaydevice

If the user selects the tuner, no further connection needs to becreated.

If the user activates playback of the DVCR, the display device indicatesthe existence of the connection with the tuner and asks the user whetherhe wants to cancel the existing connection. If the user agrees, theexisting connection is cancelled and a new connection from the DVCR tothe display device is established (and the playback is started)

(c) A connection exists between the DVCR type device and the displaydevice

If the user selects the tuner, the display device indicates theexistence of the connection with the DVCR and asks the user whether hewants to cancel the existing connection. If the user agrees, theexisting connection is cancelled and a new connection from the tuner tothe display device is established.

If the user activates playback of the DVCR, no further connection needsto be created.

If the user activates the stop function of the DVCR, the DVCR isdisconnected from the DTV.

(d) A connection exists between a further device and the display device

If the user selects the tuner, the display device indicates theexistence of the connection with the further device and asks the userwhether the further device should be disconnected. If the user agrees,then the existing connection is cancelled and a new connection betweenthe tuner and the display device is established.

If the user activates the playback function of the DVCR device, thedisplay device indicates the existence of the connection with thefurther device and asks the user whether the further device should bedisconnected. If the user agrees, then the existing connection iscancelled and a new connection between the DVCR and the display deviceis established.

The only tasks performed by the user are the choice of a function (tunerselection, playback . . . ) and, if necessary, the confirmation of thecancellation of a stream.

The example described in relation to FIG. 2 specifically makes use of aHavlet downloaded from CED-B to display a GUI at CED-A. Alternatively, aGUI may well be created by executing specific software in CED-A insteadof the Havlet. The specific software may for example be supplied by amanufacturer of CED-A and be designed to make available functions ofdevices connected to the digital network. The specific software makesthe functions of CED-B available once CED-B is registered with CED-A. Inthe case of executing the specific software instead of the Havlet, themethod for establishing a default data flow connection remains similarto the method described in relation to FIG. 2. It is possible to adaptthe behaviour of the software according to the source type.

Referring again to FIG. 1, a further device CED-C is connected to thedigital home network. CED-C is specialized in playback of Audio data. Asimilar process as previously described for CED-B may be applied toestablish a default data flow connection between CED-C and CED-A inorder to use CED-A for rendering Audio data when the play function ofCED-C is activated. In this case CED-C registers with CED-A and a usermay select CED-C on the display of CED-A. A Havlet is downloaded fromCED-C to CED-A and a GUI displayed. The user may select functions ofCED-C through this GUI. Any output from CED-C is automatically directedto the audio rendering in CED-A through the default data flowconnection, since the user selection was made through CED-A, which alsohas the rendering or display capability. The same tests for pre-existingconnections may apply in the present case.

An optional device CED-D maybe connected to the digital data bus 101 toexpand the digital home network. The CED-D is specialized in HighFidelity sound rendering.

If CED-C is connected, a default data flow connection between CED-C andCED-D may be established to render audio data. The data flow connectionis established in case the user selects a function of CED-D through anappropriate user interface on CED-D. The user interface may be theresult of downloading and processing a Havlet from CED-C to CED-D.Alternatively CED-D may execute another user interface, for example astandardized user interface of the CED-D manufacturer that makesavailable functions of CED-C, without downloading a Havlet.

A further advantage of the invention becomes apparent when a second AVrendering device CED-AA is connected to the digital home network (notshown in FIG. 1), and CED-AA is located in a different room of the homethan CED-A. In this case CED-B is also known to CED-AA and may thereforebe selected by a user of CED-AA. Upon selection, the CED-B Havlet isdownloaded to CED-AA to produce a GUI. The user sends a play instructionthrough the GUI and a default data flow connection is establishedbetween CED-B and CED-AA.

Hence a default data connection is always automatically establishedbetween the rendering device being used by the user and the CED-Bdevice. The user may select functions of CED-B on any rendering device,for example on anyone of a plurality of devices in different rooms of ahome without explicitly setting up a data connection. The latter isautomatically solved by the invention as described. The output of CED-Bis rendered on the device currently used by the user.

While the examples described herein concern electronic equipmentconnected via the IEEE 1394 bus the invention may be similarly appliedto electronic equipment used in a system connected via another type ofcommunication bus.

While mainly playback type functions have been described in theembodiment, the invention is not limited to such functions. In the casea user wishes to record a stream on a recording device (such as the DVCRmentioned above), he may achieve automatic connection of the streamsource to the display device, in order to be able to check what is beingrecorded. Similar conditions relating to pre-existing connection can beapplied. The connection between the source device and the recordingdevice can be established through other means (e.g. by selecting theDVCR as a target through the user interface).

Having described preferred embodiments of the invention with referenceto the accompanying drawings, it is to be understood that the inventionis not limited to these precise embodiments and that various changes andmodifications could be effected therein by a person skilled in the artwithout departing from the spirit or scope of the invention as definedin the appended claims.

1. Sink device for connection to a digital network (100) comprisingmeans for displaying a user interface for controlling a data sourcedevice connected to the network; further comprising: means forcontrolling network resource allocation and for automaticallyestablishing, upon selection a function of the source device by the userthrough the user interface, a connection between the data source deviceand the data sink device as default destination device of theconnection, wherein said sink device has playback capability of the dataof the source device.
 2. The device according to claim 1, wherein theconnection is an isochronous transmission connection comprisingallocation of a channel and of bandwidth.
 3. The device according toclaim 1, wherein the controlling means of the sink device carry out acheck for an existing connection from the source device to another sinkdevice, and in the affirmative, do not automatically set up theconnection between the source device and the sink device.
 4. The deviceaccording to one of the claim 1 wherein said function is a playbackfunction.
 5. The device according to claim 4, wherein said source devicecomprises a storage means for storing data to be transmitted, saidstorage means being responsive to controls for starting and stoppingreading from the storage means.
 6. The device according to one of theclaim 1, wherein said function is a selection function of the sourcedevice.
 7. The device according to claim 6, wherein said source devicecomprises a data generation means adapted to the continuous output ofdata.
 8. The device according to claim 1, further comprising memory forstoring software downloaded from the source device, wherein saidsoftware is adapted to control the automatic establishment of theconnection between the source device and the sink device and whereinsaid user interface is derived from said software.
 9. The deviceaccording to claim 8, wherein said software is a HAVi Havlet and thenetwork is a HAVi network.
 10. Method for setting up a data streamconnection in a digital network comprising a source device and a sinkdevice, said method comprising the steps of: executing a user interfaceon the sink device; selecting a function of the source device throughthe user interface; establishing a connection for data transmission fromthe data source device to the data sink device as default destinationdevice of the connection, wherein said sink device has playbackcapability of the data of the source device.
 11. The method according toclaim 10, further comprising the step of deriving the user interfacefrom software downloaded by the sink device from the source device. 12.The method according to claim 11, wherein the network is a HAVi networkand the software is a HAVi Havlet.
 13. The method according to claim 11,wherein the downloaded software controls the establishment of theconnection.
 14. The method according to claim 10, further comprising thestep, prior to establishing the connection, of verifying the existenceof a preexistent connection between the source device and a further sinkdevice, and carrying of the connection establishment step only in thenegative.
 15. The method according to claim 10, wherein said function isa playback function, and said source device is a data storage device.16. Data source device for connection to a communication networkcomprising at least one sink device, said data source device comprisingsoftware for downloading by a sink device, said software providingcontrol functions of the data source device for access by a user throughthe sink device, wherein said software is adapted to the control ofautomatically establishing, upon selection of a data reproductionfunction by a user, a connection for transmission of data from the datasource device to the sink device on which the reproduction function wasselected.